Alkaline thermostable pectinase enzyme from Aspergillus niger strain MCAS2 isolated from Manaslu Conservation Area, Gorkha, Nepal

Abstract

Pectinase enzymes are one of the commercially important enzymes having great potential in various industries especially in food industry. Pectinases accounts for 25 % of global food enzymes produced and their market is increasing day by day. Therefore, the exploration of microorganism with novel characteristics has always been the focus of the research. Microorganism dwelling in unique habitat may possess unique characteristics. As such, a pectinase producing fungus Aspergillus niger strain MCAS2 was isolated from soil of Manaslu Conservation Area (MCA), Gorkha, Nepal. The optimum production of pectinase enzyme was observed at 48 h of fermentation. The pectinase enzyme was partially purified by cold acetone treatment followed by Sephadex G-75 gel filtration chromatography. The partially purified enzyme exhibited maximum activity 60 U/mg which was almost 8.5-fold higher than the crude pectinase. The approximate molecular weight of the enzyme was found to be 66 kDa as observed from SDS-PAGE. The pectinase enzyme was active at broad range of temperature (30–70 °C) and pH (6.2–9.2). Optimum temperature and pH of the pectinase enzyme were 50 °C and 8.2 respectively. The enzyme was stable up to 70 °C and about 82 % of pectinase activity was still observed at 100 °C. The thermostable and alkaline nature of this pectinase can meet the demand of various industrial processes like paper and pulp industry, in textile industry, fruit juice industry, plant tissue maceration and wastewater treatment. In addition, the effect of different metal ions on pectinase activity was also studied.

Partial Purification and Characterisation of Pectinase Produced by Aspergillus niger LFP-1 Grown on Pomelo Peels as a Substrate

“… Ire and Vinking (2016) reported that the polygalacturonase from A. niger grown on banana peels was purified up to 42 folds with 166.67 U/mg of specific activity trough gel filtration on Sephadex 100. On the other hand, the pectinase from A. niger strain MCAS2 was purified 8.5-folds with a specific activity of 60 U/mg by using Sephadex G-75 gel filtration chromatography ( Khatri et al 2015 ). Overall, the purification steps demonstrate a decrease in total activity and total protein.…”

Micro- and nano-capsulated fungal pectinase with outstanding capabilities of eliminating turbidity in freshly produced juice

“…The eluted fractions from chromatography onto Sephadex G-100 resulted in 69.41% of the original activity with a purification fold of 6.39 (Table 1). Khatri et al (2015) showed that the pectinase enzyme from Aspergillus niger strain MCAS2 was purified 1.2fold with specific activity of 8.33 U/mg by using cold acetone purification method and 8.5-fold with specific activity of 60 U/mg by using Sephadex method.…”

“…Khatri et al . (2015) showed that the pectinase enzyme from Aspergillus niger strain MCAS2 was purified 1.2-fold with specific activity of 8.33 U/mg by using cold acetone purification method and 8.5-fold with specific activity of 60 U/mg by using Sephadex method.…”

Optimisation of alkaline pretreatment conditions of orange and plantain peels for polygalacturonase production by Aspergillus awamori CICC 2040

“…al., 2014). Polygalacturonase has been produced via solid-state fermentation (SSF) and submerged fermentation (SF) processes (Khatri et. al., 2015).…”